The knowledge most lacking among believers today concerns the existence of the human spirit and its function. Many believers do not know they have a spirit in addition to their mind, emotion, and will. Even after hearing that there is a spirit within man, they either think that their mind, emotion, or will is the spirit, or they are puzzled and do not know where their spirit is. This ignorance is a very serious matter. Because of this, believers do not know how to cooperate with God, control themselves, and fight against Satan, since all these three things require the work of the spirit.
The most important thing that a believer should know is that there is a spirit within him besides the thought, knowledge, and imagination of the mind; the feeling, love, and desire of the emotion; and the ideas, opinion, and determination of the will. The spirit is deeper than the mind, emotion, and will. A believer should know that he has a spirit; he also should know the feeling of the spirit, its working, its power, and the principle of its activity. Only in this way will a believer be able to know how to walk according to the spirit, not according to the fleshly soul or body.
An unregenerated person's spirit and soul are constituted together. Naturally, he only knows the feelings of the soul, which are strong and powerful, and does not know the existence of the spirit, which is dead and dormant. This ignorance started when he was a sinner and continues even after he becomes a believer. Although a believer has life in his spirit and the experience of overcoming "fleshly things," he sometimes walks according to the spirit and sometimes according to the soul. He does not know what the spirit demands, how the spirit initiates, or how to nourish the spirit. He does not know the feeling of the spirit and the meaning that these feelings represent. Naturally, he restricts the life of the spirit and lets the natural life of the soul continue to act as the principle of his living. This matter is very serious; it is beyond the common believer's imagination. There are some believers who faithfully seek higher and deeper spiritual experience. After they have the experience of overcoming sins, they no longer go forward because they do not know the work of the spirit. Instead, they pursue after "spiritual and biblical knowledge" in their mind; they seek after the Lord's presence in their feelings and a kind of burning feeling in their members; and they mostly behave and walk according to the power of their own will. This causes the believer to be deceived and over-emphasize his own (soulish) experience, thinking himself to be super-spiritual. This will cultivate his "self" life (soul) to a great extent. He subjectively thinks that his experience is spiritually solid, which will keep him from progressing in the spiritual path. Therefore, God's children should humble themselves before God, subject themselves to the Holy Spirit and biblical teachings, and gradually examine the function and work of the spirit in order that they may walk according to the spirit.